This invention relates to grafts for use in the repair, replacement or supplement of a medical patient's natural body organ structures or tissues. More particularly, this invention relates to a graft with a suture connector for use in vascular anastomosis (the surgical connection of vessels).
An example of the possible uses of the invention is a minimally invasive cardiac bypass procedure. This and other examples are considered in detail in David S. Goldsteen et al., U.S. patent application Ser. No. 08/745,618, filed Nov. 7, 1996, which is incorporated herein by reference.
Vascular anastomosis is a delicate and time-consuming procedure. Conventional anastomosis using a graft requires placement of fine sutures circumferentially around the vessel at the anastomosis (vessel attachment) site.
Conventional anastomosis using graft suturing, as shown in FIG. 1a, may have certain limitations. First, the anastomosis created may be non-compliant (i.e., the graft may not readily expand or contract radially). This may produce a compliance mis-match between the graft and the native vessel. As the native vessel expands or contracts under hemodynamic pressure, the suture site tends to remain more nearly rigid, producing high stress which may eventually result in tissue and/or graft deterioration, as shown for the graft in FIG. 1b. Second, the selection of materials for grafts is necessarily limited to those materials of sufficient tensile strength in order to withstand suturing. For example, a well-known bio-compatible and bio-stable material such as silicone has not been used to its full potential in grafts because of its limited mechanical ability to retain sutures.
In view of the foregoing, it is an object of the present invention to provide a graft which is compliant at the anastomosis site.
It is also an object of the present invention to provide a graft which is formed from a material which is bio-compatible and bio-stable.